Answer:
A) The area of circle is 2.54 mm²
B) The area of circle is 1533.60 mm²
Step-by-step explanation:
Given as :
A ) circumference of circle = 12 cm
∵ circumference of circle is [tex]2\times \Pi \times radius[/tex]
Or, 12 = [tex]2\times \Pi \times radius[/tex]
Or, Radius of circle = [tex]\frac{12}{2\times 3.14}[/tex]
Or, Radius of circle = [tex]\frac{6}{ 3.14}[/tex]
∴ Radius of circle = 1.91 cm
Now, The radius of circle is decrease by 2
So, New radius R = 1.91 - 2 = - 0.09 cm
∴ The area of circle = [tex]\Pi \times radius^{2}[/tex]
Or, The area of circle = 3.14 × ( - 0.09 )²
C' = 0.0254 cm² = 2.54 mm²
B ) The area of circle = 251 mm²
The radius of circle is increase by 3 mm
So, R' = 1.91 cm + 3 mm
Or, R' = ( 1.91 × 10 ) mm + 3 mm
Or, R' = 22.1 mm
So, Area of new circle C'' = [tex]\Pi \times radius^{2}[/tex]
Or, C'' = [tex]\Pi \times (22.1)^{2}[/tex]
Or, C'' = 1533.60 mm²
Hence , A) The area of circle is 2.54 mm²
B) The area of circle is 1533.60 mm² Answer
